... put that unto the affected box (if it's Unix),
build the cf file (using a command similar to the
one we used on the Linux box --- finding the right
directory is the trick. You could use the copy
of sendmail on the Linux box to build the .cf files
for the other system(s) --- just redirect the
m4 output to another file and copy the file over using
ftp/rcp (or whatever).

... Note: Change the OSTYPE argument as appropriate.

If this is a Windows box running Netscape Communicator
or something like that -- check your "Identity" on
that system.

We know that you system will currenly relay for anyone
that "claims" to be sending mail "from" your domain.
So any client that masquerades as williams-consulting.com
should work.

I'll get an answer about the appropriate format for the
/etc/mail/{relay_allow} file tonight. I'm pretty sure
I have examples from Glynn Clements' posting to linux-admin
in my archives.